When approval manager of a record is changed to another approval manager, wehther previous approval manager can track the request status?

Yes. We can enable the setting key - Enable or Disable Approval Manager Change Ticket View. If this setting key is enabled, approval manager can access the tickets of his ownership changed to another.

Once this option is enabled, when we try to change the approval manager user will get an option - Enable Approval Manager to track this request. Check this check box and change the approval manager.

In ticket list/grid view user will get an option to view the list of tickets.

Note: This feature is available only in New UI